package qingke.chat;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class UsernameListServlet
 */
@WebServlet("/UsernameListServlet")
public class UsernameListServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public UsernameListServlet() {
        super();
        // TODO Auto-generated constructor stub
    }

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		response.setCharacterEncoding("UTF-8");
		List<String> usernames = (List<String>)request.getServletContext().getAttribute("usernameList");
		if(usernames ==null){
			usernames = new ArrayList<String>();
			System.out.println("user name list is null, init");
		}
		String line ="";
		for (String name : usernames) {
			line += name + ",";
			
		}
		line = line.equals("") ? line : line.substring(0, line.length() -1);
		response.getWriter().append(line);
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
	}

}
